It really depends on how you define "singer". If you are talking purely about vocal talents (as they assess it on shows like American Idol) then that matters not a lick to me...would I rather listen to someone with a technically "perfect" voice sing weak songs or Bob Dylan...no contest.

So I guess my answer would be both....I like artists who write songs that fit their voice.

the song is more important. If the song has, first and foremost, a good melody, and also decent lyrics, good various instrument parts, etc, than thats what matters most. Plus, id rather hear a song sung by artists that dont have great voices in the commercial sense, but speak from the heart - Neil Young, Bob Dylan, Tom Waits, John Frusciante, and so on. That even adds to the song to me. So singer is important, but i like songs written by these artists sung by other musicians still, so song comes first for me. Except in rare instances that i cant stand a singers voice so much that i dont want to listen to the song, like with Robert Plant.

The song. There are examples of voices I cant stand (Dylan, Fogerty, Springsteen) that have a song or two I can tolerate just because they are good songs. I'd rather hear other people sing the majority of their songs though.

__________________Donovan: If he (Paul McCartney) fell on the piano, by the time he picked himself up he would have written three songs.

The singer. I can hear my favorite songs done by other singers and find them to be just HORRIBLE when they've covered them. But then again, if the song is shite to begin with, it may not get much better. But I think a truly grandiose singer would be able to make diamonds out of nothing when it all comes down to it